Bluetooth: Fix code style warning

Output of checkpatch shows warning:
drivers/bluetooth/bfusb.c:368: WARNING: braces {} are not necessary
for single statement blocks

Remove braces for single line statement.

Signed-off-by: Jeremy Clifton <deaner92@yahoo.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>